CN110873954B - Display system, electron mirror system, and moving object - Google Patents

Display system, electron mirror system, and moving object Download PDF

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Publication number
CN110873954B
CN110873954B CN201910812410.9A CN201910812410A CN110873954B CN 110873954 B CN110873954 B CN 110873954B CN 201910812410 A CN201910812410 A CN 201910812410A CN 110873954 B CN110873954 B CN 110873954B
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China
Prior art keywords
light
display system
final
display device
image
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CN201910812410.9A
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Chinese (zh)
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CN110873954A (en
Inventor
今村典广
山形道弘
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Panasonic Automotive Electronic Systems Co ltd
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Panasonic Intellectual Property Management Co Ltd
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Priority claimed from JP2019073828A external-priority patent/JP6697754B2/en
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    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B17/00—Systems with reflecting surfaces, with or without refracting elements
    • G02B17/02—Catoptric systems, e.g. image erecting and reversing system
    • G02B17/06—Catoptric systems, e.g. image erecting and reversing system using mirrors only, i.e. having only one curved mirror
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60R—VEHICLES, VEHICLE FITTINGS, OR VEHICLE PARTS, NOT OTHERWISE PROVIDED FOR
    • B60R1/00—Optical viewing arrangements; Real-time viewing arrangements for drivers or passengers using optical image capturing systems, e.g. cameras or video systems specially adapted for use in or on vehicles
    • B60R1/02—Rear-view mirror arrangements
    • B60R1/08—Rear-view mirror arrangements involving special optical features, e.g. avoiding blind spots, e.g. convex mirrors; Side-by-side associations of rear-view and other mirrors
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60R—VEHICLES, VEHICLE FITTINGS, OR VEHICLE PARTS, NOT OTHERWISE PROVIDED FOR
    • B60R1/00—Optical viewing arrangements; Real-time viewing arrangements for drivers or passengers using optical image capturing systems, e.g. cameras or video systems specially adapted for use in or on vehicles
    • B60R1/02—Rear-view mirror arrangements
    • B60R1/04—Rear-view mirror arrangements mounted inside vehicle
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60R—VEHICLES, VEHICLE FITTINGS, OR VEHICLE PARTS, NOT OTHERWISE PROVIDED FOR
    • B60R1/00—Optical viewing arrangements; Real-time viewing arrangements for drivers or passengers using optical image capturing systems, e.g. cameras or video systems specially adapted for use in or on vehicles
    • B60R1/02—Rear-view mirror arrangements
    • B60R1/06—Rear-view mirror arrangements mounted on vehicle exterior
    • B60R1/062—Rear-view mirror arrangements mounted on vehicle exterior with remote control for adjusting position
    • B60R1/07—Rear-view mirror arrangements mounted on vehicle exterior with remote control for adjusting position by electrically powered actuators
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60R—VEHICLES, VEHICLE FITTINGS, OR VEHICLE PARTS, NOT OTHERWISE PROVIDED FOR
    • B60R1/00—Optical viewing arrangements; Real-time viewing arrangements for drivers or passengers using optical image capturing systems, e.g. cameras or video systems specially adapted for use in or on vehicles
    • B60R1/02—Rear-view mirror arrangements
    • B60R1/08—Rear-view mirror arrangements involving special optical features, e.g. avoiding blind spots, e.g. convex mirrors; Side-by-side associations of rear-view and other mirrors
    • B60R1/083—Anti-glare mirrors, e.g. "day-night" mirrors
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60R—VEHICLES, VEHICLE FITTINGS, OR VEHICLE PARTS, NOT OTHERWISE PROVIDED FOR
    • B60R1/00—Optical viewing arrangements; Real-time viewing arrangements for drivers or passengers using optical image capturing systems, e.g. cameras or video systems specially adapted for use in or on vehicles
    • B60R1/12—Mirror assemblies combined with other articles, e.g. clocks
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60R—VEHICLES, VEHICLE FITTINGS, OR VEHICLE PARTS, NOT OTHERWISE PROVIDED FOR
    • B60R1/00—Optical viewing arrangements; Real-time viewing arrangements for drivers or passengers using optical image capturing systems, e.g. cameras or video systems specially adapted for use in or on vehicles
    • B60R1/20—Real-time viewing arrangements for drivers or passengers using optical image capturing systems, e.g. cameras or video systems specially adapted for use in or on vehicles
    • B60R1/22—Real-time viewing arrangements for drivers or passengers using optical image capturing systems, e.g. cameras or video systems specially adapted for use in or on vehicles for viewing an area outside the vehicle, e.g. the exterior of the vehicle
    • B60R1/23—Real-time viewing arrangements for drivers or passengers using optical image capturing systems, e.g. cameras or video systems specially adapted for use in or on vehicles for viewing an area outside the vehicle, e.g. the exterior of the vehicle with a predetermined field of view
    • B60R1/26—Real-time viewing arrangements for drivers or passengers using optical image capturing systems, e.g. cameras or video systems specially adapted for use in or on vehicles for viewing an area outside the vehicle, e.g. the exterior of the vehicle with a predetermined field of view to the rear of the vehicle
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B5/00—Optical elements other than lenses
    • G02B5/30—Polarising elements
    • G02B5/3025—Polarisers, i.e. arrangements capable of producing a definite output polarisation state from an unpolarised input state
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B5/00—Optical elements other than lenses
    • G02B5/30—Polarising elements
    • G02B5/3083—Birefringent or phase retarding elements
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60R—VEHICLES, VEHICLE FITTINGS, OR VEHICLE PARTS, NOT OTHERWISE PROVIDED FOR
    • B60R11/00—Arrangements for holding or mounting articles, not otherwise provided for
    • B60R11/02—Arrangements for holding or mounting articles, not otherwise provided for for radio sets, television sets, telephones, or the like; Arrangement of controls thereof
    • B60R11/0229—Arrangements for holding or mounting articles, not otherwise provided for for radio sets, television sets, telephones, or the like; Arrangement of controls thereof for displays, e.g. cathodic tubes
    • B60R11/0235—Arrangements for holding or mounting articles, not otherwise provided for for radio sets, television sets, telephones, or the like; Arrangement of controls thereof for displays, e.g. cathodic tubes of flat type, e.g. LCD
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60R—VEHICLES, VEHICLE FITTINGS, OR VEHICLE PARTS, NOT OTHERWISE PROVIDED FOR
    • B60R1/00—Optical viewing arrangements; Real-time viewing arrangements for drivers or passengers using optical image capturing systems, e.g. cameras or video systems specially adapted for use in or on vehicles
    • B60R1/12—Mirror assemblies combined with other articles, e.g. clocks
    • B60R2001/1215—Mirror assemblies combined with other articles, e.g. clocks with information displays
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60R—VEHICLES, VEHICLE FITTINGS, OR VEHICLE PARTS, NOT OTHERWISE PROVIDED FOR
    • B60R2300/00—Details of viewing arrangements using cameras and displays, specially adapted for use in a vehicle
    • B60R2300/20—Details of viewing arrangements using cameras and displays, specially adapted for use in a vehicle characterised by the type of display used
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60R—VEHICLES, VEHICLE FITTINGS, OR VEHICLE PARTS, NOT OTHERWISE PROVIDED FOR
    • B60R2300/00—Details of viewing arrangements using cameras and displays, specially adapted for use in a vehicle
    • B60R2300/80—Details of viewing arrangements using cameras and displays, specially adapted for use in a vehicle characterised by the intended use of the viewing arrangement
    • B60R2300/8046—Details of viewing arrangements using cameras and displays, specially adapted for use in a vehicle characterised by the intended use of the viewing arrangement for replacing a rear-view mirror system

Abstract

The present disclosure provides a display system, an electronic mirror system, and a mobile object that can be miniaturized. The display system (10) has at least a first reflective surface (31) and a second reflective surface (41) between the display device (20) and the final reflective surface (51). The first reflecting surface (31) reflects light emitted from the display device (20) toward the second reflecting surface (41), and the second reflecting surface (41) reflects light reflected from the first reflecting surface (31) toward the final reflecting surface (51). Before light emitted from the display device (20) reaches the final reflection surface (51), an optical path for propagating light from the display screen (21) of the display device (20) to the first reflection surface (31) intersects an optical path for propagating light from the second reflection surface (41) to the final reflection surface (51).

Description

Display system, electron mirror system, and moving object
Technical Field
The invention relates to a display system, an electron mirror system, and a mobile body. More specifically, the present disclosure relates to a display system that displays an image, an electronic mirror system, and a moving object.
Background
Conventionally, there is a display device (display system) for a vehicle including a rear camera, a monitor, and a concave mirror (see, for example, japanese patent application laid-open No. 2009-120080 (hereinafter, referred to as "document 1")). The rear camera is used for shooting the rear of the vehicle. The monitor is provided at a ceiling position between a driver's seat and a passenger seat in the vehicle cabin, and displays a vehicle rear image based on vehicle rear image data from the rear camera. The concave mirror is provided at an upper position of a windshield in a vehicle interior, and reflects a monitor image to allow a vehicle occupant to view an image behind the vehicle.
Disclosure of Invention
Problems to be solved by the invention
In the vehicle display device described in patent document 1, in order to reduce the moving distance of the focal point of the vehicle occupant between the case where the vehicle occupant views the front of the vehicle and the case where the vehicle occupant views the image reflected on the concave mirror, it is necessary to increase the visual distance between the visual point of the vehicle occupant and the image visually recognized by the vehicle occupant. In order to increase the visual distance between the point of view of the vehicle occupant and the image visually recognized by the vehicle occupant, it is necessary to increase the distance between the monitor and the concave mirror. As the size of the entire vehicle display device becomes larger, the space in the vehicle cabin becomes smaller by the larger amount, and therefore downsizing of the vehicle display device has been desired.
An object of the present disclosure is to provide a display system, an electronic mirror system, and a mobile object that can be miniaturized.
Means for solving the problems
A display system according to one embodiment of the present disclosure displays a second image based on a first image displayed by a display device. The display system has at least a first reflection surface and a second reflection surface on an optical path between the display device and a final reflection surface that reflects light emitted from the display device toward the outside of the display system. The first reflective surface reflects light emitted from the display device toward the second reflective surface. The second reflecting surface reflects the reflected light from the first reflecting surface toward the final reflecting surface. Before the light emitted from the display device reaches the final reflection surface, a first optical path that propagates the light from the display screen of the display device toward the first reflection surface intersects with a second optical path that propagates the light from the second reflection surface toward the final reflection surface.
A display system according to an aspect of the present disclosure displays a second image based on a first image displayed by a display device, and includes the display device, a first optical member, a second optical member, and a final optical member. The first optical member is disposed in a manner facing the display device. The first optical member has a first reflecting surface that reflects first incident light that enters from a display screen of the display device in a first direction toward a second direction different from the first direction. The second optical member is disposed so as to face the first reflecting surface. The second optical member has a second reflecting surface that reflects second incident light that enters from the first reflecting surface in the second direction, in a third direction that is different from the second direction. The final optical member is disposed so as to face the second reflecting surface. The final optical member has a final reflecting surface that reflects third incident light incident from the second reflecting surface in the third direction. The optical path of the first incident light intersects the optical path of the third incident light.
An electronic mirror system according to one aspect of the present disclosure includes the display system and an imaging unit, and the display device displays the first image based on an imaging image of the imaging unit.
A moving object according to one aspect of the present disclosure includes the electronic mirror system and a moving object main body on which the electronic mirror system is mounted.
ADVANTAGEOUS EFFECTS OF INVENTION
According to the present disclosure, a display system, an electronic mirror system, and a mobile object that can be miniaturized are provided.
Drawings
Fig. 1 is a schematic explanatory diagram of a display system according to an embodiment of the present disclosure.
Fig. 2 is a schematic explanatory view of a mobile unit having the display system described above.
Fig. 3 is an explanatory diagram showing an example of an image displayed by the above-described display system.
Fig. 4 is an explanatory diagram of a second image displayed by the above-described display system.
Fig. 5 is a schematic explanatory diagram of a display system according to modification 1 of the embodiment of the present disclosure.
Fig. 6 is a schematic explanatory view of a display system according to modification 1.
Fig. 7 is an explanatory diagram of a polarizing element provided in the display system of modification 1.
Fig. 8 is a schematic explanatory diagram showing another mode of the display system of modification 1.
Fig. 9 is an explanatory diagram for explaining an optical path of external light incident on the display system of modification 1 from outside the display system.
Fig. 10 is a schematic explanatory diagram of a display system according to modification 2 of the embodiment of the present disclosure.
Fig. 11A is a schematic explanatory diagram of a display system according to modification 3 of the embodiment of the present disclosure.
Fig. 11B is a schematic explanatory diagram of a display system according to an embodiment of the present disclosure.
Fig. 12A is an explanatory diagram of a second image displayed by the display system according to modification 3.
Fig. 12B is an explanatory diagram of a second image displayed by the display system according to the embodiment of the present disclosure.
Fig. 13 is a schematic explanatory diagram of a display system according to modification 4 of the embodiment of the present disclosure.
Fig. 14 is a schematic explanatory diagram of a display system according to modification 5 of the embodiment of the present disclosure.
Fig. 15 is a schematic explanatory diagram of a display system according to modification 6 of the embodiment of the present disclosure.
Fig. 16 is a schematic explanatory diagram of a display system according to another modification of the embodiment of the present disclosure.
Detailed Description
Fig. 1 to 16 described in the following embodiments and the like are conceptual diagrams, and the proportions of the sizes and thicknesses of the respective components in the diagrams are not necessarily limited to those reflecting actual dimensional ratios.
(embodiment mode)
(1) Summary of the invention
As shown in fig. 1 and 2, the display system 10 according to the present embodiment is used, for example, in an automobile 100 as a mobile object.
As shown in fig. 1, the display system 10 includes a display device 20, a first reflection surface 31, a second reflection surface 41, and a final reflection surface 51.
The display system 10 has at least a first reflection surface 31 and a second reflection surface 41 on an optical path between the display device 20 and a final reflection surface 51 that reflects light emitted from the display device 20 toward the outside of the display system 10. Further, the display system 10 has a reflection optical system including a plurality of reflection surfaces 31, 41, 51, and the final reflection surface 51 is a reflection surface that finally reflects light emitted from the display device 20 in the reflection optical system.
The first reflective surface 31 reflects light emitted from the display device 20 toward the second reflective surface 41. The second reflecting surface 41 reflects the light reflected from the first reflecting surface 31 toward the final reflecting surface 51.
Before the light emitted from the display device 20 reaches the final reflection surface 51, an optical path a11 that propagates the light from the display screen 21 of the display device 20 toward the first reflection surface 31 intersects an optical path a13 that propagates the light from the second reflection surface 41 toward the final reflection surface 51.
In other words, the display system 10 includes the display device 20, a first optical member (in the present embodiment, the first reflecting mirror 30), a second optical member (in the present embodiment, the second reflecting mirror 40), and a final optical member (in the present embodiment, the final reflecting mirror 50). The first optical member is arranged in such a manner as to face the display device 20. The first optical member has a first reflecting surface 31 that reflects first incident light (light passing through an optical path a11 of fig. 1) incident in a first direction from the display screen 21 of the display device 20 in a second direction different from the first direction in which the first incident light is incident. The second optical member is disposed so as to face the first reflecting surface 31. The second optical member has a second reflecting surface 41 that reflects second incident light (light passing through the optical path a12 in fig. 1) incident from the first reflecting surface 31 in the second direction in a third direction different from the second direction. The final optical member is disposed so as to face the second reflecting surface 41. The final optical member has a final reflecting surface 51 that reflects third incident light (light passing through the optical path a13 in fig. 1) incident in the third direction from the second reflecting surface 41. The optical path a11 of the first incident light intersects the optical path a13 of the third incident light. The two surfaces or members "facing" are not limited to being arranged in parallel with each other, and may include a state in which they are not parallel with each other, that is, a state in which one surface is inclined with respect to the other surface.
Here, the display device 20, the first reflection surface 31, the second reflection surface 41, and the final reflection surface 51 are arranged so as to surround the periphery of the range 200 in which the medium that propagates light exists. The medium-existing range 200 is a range in which a medium for propagating light is filled, and may be a space or an inner portion of an optical member such as a prism formed of a material having light transmittance such as glass. In addition, the first reflecting surface 31 reflecting light emitted from the display device 20 toward the second reflecting surface 41 includes the following cases: the case where the reflected light from the first reflecting surface 31 directly enters the second reflecting surface 41; and the reflected light from the first reflecting surface 31 may enter the second reflecting surface 41 via one or more reflecting surfaces. The second reflecting surface 41 reflects the light reflected from the first reflecting surface 31 toward the final reflecting surface 51 includes the following cases: the case where the reflected light from the second reflecting surface 41 directly enters the final reflecting surface 51; and the reflected light from the second reflecting surface 41 enters the final reflecting surface 51 via one or more reflecting surfaces. In addition, the intersection of the optical path a11 with the optical path a13 is not limited to the intersection of the optical path of the outgoing light with respect to all the light outgoing from the display screen 21 of the display device 20 with the optical path of the reflected light from the second reflection surface 41. That is, at least a part of the light emitted from the display device 20, for example, the optical path a11 of the light emitted from the vicinity of the center of the display screen 21 may intersect the optical path a13 of the reflected light from the second reflecting surface 41. In other words, the optical path of at least a part of the light emitted from the display screen 21 of the display device 20 may intersect the optical path of the reflected light from the second reflecting surface 41, as viewed from the direction parallel to the optical path a11 and the direction orthogonal to the direction parallel to the optical path a13, respectively.
In fig. 1, light paths a11 to a14 before light emitted from the vicinity of the center of the display screen 21 of the display device 20 is reflected by the final reflection surface 51 and output to the outside of the display device 20 are shown by broken lines. In fig. 1, lines indicating the light passing range 200, the light paths a11 to a14 of the light passing through the range 200, the length L1, and the like are illustrated for explanation only and are not actually shown.
In the present embodiment, before the light emitted from the display device 20 reaches the final reflection surface 51, the optical path a11 that propagates the light from the display screen 21 of the display device 20 toward the first reflection surface 31 intersects the optical path a13 that propagates the light from the second reflection surface 41 toward the final reflection surface 51. As such, since the optical path a11 intersects the optical path a13, the optical path length from the display device 20 to the final reflection surface 51 becomes longer if the number of reflections is the same, compared to the case where light propagates in an optical path along the periphery of the range 200. Thus, it is possible to increase the optical path length from the display device 20 to the final reflection surface 51 and also to reduce the length L1 from the second reflection surface 41 to the final reflection surface 51, so that downsizing of the display system 10 can be achieved. Therefore, it is possible to increase the visual distance from the viewpoint of the user 400 of the display system 10 to the image (virtual image) displayed on the final reflection surface 51, and to achieve downsizing of the display system 10.
In the following embodiments, the case where the first optical member, the second optical member, and the final optical member are independent optical members will be described as an example, but some or all of the first optical member, the second optical member, and the final optical member may be integrated. Further, the first optical member, the second optical member, and the final optical member are each a mirror, but the first optical member, the second optical member, and the final optical member may be prisms. That is, the first reflecting surface 31, the second reflecting surface 41, and the final reflecting surface 51 may be realized by, for example, reflecting surfaces of prisms, and a plurality of reflecting surfaces among the first reflecting surface 31, the second reflecting surface 41, and the final reflecting surface 51 may be realized by a plurality of reflecting surfaces included in one prism.
(2) Detailed description of the invention
Next, the display system 10 according to the present embodiment will be described in detail with reference to the drawings.
(2.1) Structure
As shown in fig. 1, the display system 10 of the present embodiment includes a display device 20, a first mirror 30 having a first reflecting surface 31, a second mirror 40 having a second reflecting surface 41, and a final mirror 50 having a final reflecting surface 51. The display system 10 further includes a display control unit 22 and a housing 70.
The electronic mirror system 80 is configured by the display system 10 and the imaging unit 90 (see fig. 2) of the present embodiment, and the display device 20 displays a first image based on the captured image of the imaging unit 90. The electronic mirror system 80 is mounted on a moving body main body 110 of an automobile 100 as a moving body. That is, the mobile body (automobile 100) includes the electronic mirror system 80 and a mobile body main body 110 on which the electronic mirror system 80 is mounted.
The housing 70 is made of, for example, a synthetic resin molded product. The housing 70 is formed in a rectangular parallelepiped shape having a housing chamber 73 therein. The housing 70 is formed in the following shape: in a state of being attached to the moving body main body 110, a dimension in the left-right direction (vehicle width direction) of the moving body main body 110 is larger than a dimension in the up-down direction and a dimension in the front-rear direction. The housing chamber 73 of the housing 70 houses the display device 20, the first reflecting mirror 30, the second reflecting mirror 40, the final reflecting mirror 50, and the display control unit 22.
The housing 70 is mounted on a ceiling portion 101 of the moving body main body 110 at a position close to a front side portion of a windshield 102 (front window glass) and entering a field of view of a user 400 seated on a front seat (see fig. 2). The housing 70 is attached to the ceiling portion 101 of the moving body main body 110 in a suspended state from the ceiling portion 101 via a support member 72 such as a ball joint, and is disposed at a position not obstructing the forward visual field of the user 400. In fig. 1 and 2, a support member is disposed on the upper portion of the housing 70 and suspended from the ceiling portion 101, but the support member may be disposed on the rear surface side (vehicle front side) of the housing 70 and attached to the windshield 102.
An opening 71 penetrating the rear wall of the housing 70 is provided on the surface of the rear portion of the housing 70 (that is, the rear wall of the housing 70). The dimension of the opening 71 in the left-right direction (the direction orthogonal to the up-down direction and the front-back direction) is larger than the dimension in the up-down direction, and the ratio between the dimension in the up-down direction (the dimension of the short side) and the dimension in the left-right direction (the dimension of the long side) is about 3: 1-6: 1.
the display device 20 is housed in a lower portion of the housing chamber 73 in a state in which the display screen 21 is directed upward. The display device 20 will form the light output of the first image. The Display device 20 includes, for example, a light source device and a Liquid Crystal panel (LCD). The liquid crystal panel is disposed in front of the light source device. The light source device is used as a backlight of the liquid crystal panel. The light source device is a so-called surface light source. The light source device is a sidelight type light source device using a solid-state light emitting element such as a light emitting diode or a laser diode. Light from the light source device is transmitted through the liquid crystal panel and then output from the display screen 21 of the display device 20, and a first image is formed by the light output from the display screen 21 of the display device 20. Here, the exit angle of the light emitted from the display screen 21 of the display device 20 is determined by adjusting, for example, the exit angle of the light output from the light source device.
The display system 10 of the present embodiment includes a reflection optical system B1, and the reflection optical system B1 is composed of three mirrors, i.e., a first mirror 30 having a first reflection surface 31, a second mirror 40 having a second reflection surface 41, and a final mirror 50 having a final reflection surface 51. Here, the display device 20, the first mirror 30, the second mirror 40, and the final mirror 50 are disposed around the medium-existing range 200 inside the housing chamber 73.
The first reflecting mirror 30 is, for example, a flat mirror. The first reflecting surface 31 of the first reflecting mirror 30 is formed by depositing a reflective metal film such as aluminum on the surface of glass, for example. The first reflecting mirror 30 is disposed above the housing chamber 73 with the first reflecting surface 31 facing downward. That is, the display screen 21 of the display device 20 and the first reflection surface 31 face each other across the range 200. In the present embodiment, the first reflecting surface 31 of the first reflecting mirror 30 is a flat surface, but the first reflecting surface 31 may be a curved surface such as a free curved surface. By forming the first reflecting surface 31 as a free curved surface, it is possible to reduce image distortion of the second image formed on the final reflecting surface 51, reduce curvature of the image plane, or improve resolution.
In the present embodiment, the display device 20 and the first reflecting mirror 30 are arranged in such a manner that the display screen 21 is substantially parallel to the first reflecting surface 31, so that the size of the housing 70 in the up-down direction can be reduced. Here, the two surfaces "parallel" are not limited to a state where the two surfaces do not intersect at all, and may intersect at an angle of about several degrees as long as the human eyes look substantially parallel to each other.
The second reflecting mirror 40 has light transmissivity. The second reflecting mirror 40 is formed of a beam splitter formed in a flat plate shape, and the second reflecting surface 41 is a surface of the beam splitter. That is, the light transmissive reflecting surface (in the present embodiment, the second reflecting surface 41) of at least one of the first reflecting surface 31 and the second reflecting surface 41 is a surface of the beam splitter. In other words, at least one of the first reflecting surface 31 and the second reflecting surface 41 is a surface of a light-transmissive optical member having light permeability for transmitting a part of incident light. The reflected light from the final reflecting surface 51 is transmitted through the translucent optical member and is emitted to the outside of the display system 10. In the present embodiment, the second reflecting mirror 40 is a light-transmissive optical member, for example, a beam splitter. That is, the light-transmissive optical component includes a beam splitter.
The second reflecting mirror 40 has a function of transmitting a part of incident light and reflecting another part of the incident light. In the present embodiment, the second reflecting mirror 40 is configured by forming a half mirror having a light transmittance and a light reflectance of about 50% on the second reflecting surface 41 (hereinafter, also referred to as an inner surface), for example. The second mirror 40 is also configured as a beam splitter. The second reflecting mirror 40 is attached to the opening 71 of the housing 70 and is disposed at a position adjacent to the display screen 21 and the first reflecting surface 31 of the display device 20, respectively. In the second reflecting mirror 40, the second reflecting surface 41 on the side of the housing chamber 73 and the outer surface 42 facing the outside of the housing 70 are flat surfaces. Here, the second reflecting mirror 40 is disposed such that the normal direction of the second reflecting surface 41 intersects obliquely with respect to the incident direction of the light from the first reflecting surface 31 and the incident direction of the light from the final reflecting surface 51. The incident direction of the incident light from the first reflecting surface 31 is a direction parallel to the optical path a12 of fig. 1, and the incident direction of the incident light from the final reflecting surface 51 is a direction parallel to the optical path a14 of fig. 1. In the present embodiment, the second reflecting surface 41 of the second reflecting mirror 40 is a flat surface, but the second reflecting surface 41 may be a curved surface such as a free curved surface. By forming the second reflecting surface 41 as a free-form surface, it is possible to reduce image distortion of the second image formed on the final reflecting surface 51, reduce curvature of the image surface, or improve resolution.
The final mirror 50 is, for example, a concave mirror. The final reflecting surface 51 of the final reflecting mirror 50 is formed by depositing a reflective metal film such as aluminum on the surface of glass, for example. The final reflecting mirror 50 is disposed in the storage chamber 73 at a position facing the second reflecting mirror 40 with the range 200 therebetween. The final reflecting mirror 50 is disposed in the housing chamber 73 with the final reflecting surface 51 facing rearward, and the final reflecting surface 51 of the final reflecting mirror 50 and the second reflecting surface 41 of the second reflecting mirror 40 face each other with the range 200 interposed therebetween. The final reflecting surface 51 of the final reflecting mirror 50 is disposed at a position adjacent to each of the display screen 21 and the first reflecting surface 31 of the display device 20. The final reflecting mirror 50 is not limited to the concave mirror, and may be a plane mirror.
In the present embodiment, the first reflective surface 31 reflects light emitted from the display device 20 toward the second reflective surface 41. The second reflecting surface 41 reflects the light reflected from the first reflecting surface 31 toward the final reflecting surface 51. That is, the light emitted from the display device 20 is reflected by the first reflection surface 31 and the second reflection surface 41 in this order, and then enters the final reflection surface 51.
The final reflecting surface 51 reflects the light reflected from the second reflecting surface 41 toward the second reflecting surface 41. In the present embodiment, the second reflecting surface 41 is formed by a surface of a second optical member (for example, a beam splitter or the like) that transmits a part of incident light. That is, the second optical member having the second reflecting surface 41 has light transmissivity for transmitting a part of the incident light, and the second optical member is a light-transmissive optical member. When the final reflection surface 51 reflects the incident light toward the second reflection surface 41, the reflected light from the final reflection surface 51 passes through the second reflection surface 41 and is emitted to the outside of the display system 10. Thus, when the first image is displayed in the display device 20, the second image reflected by the final reflecting surface 51 is visually recognized as a virtual image by the user 400 (e.g., a passenger such as a driver of the automobile 100) after passing through the second reflecting mirror 40 (beam splitter) having the second reflecting surface 41. That is, the user 400 sees the image reflected by the first reflecting surface 31, the second reflecting surface 41, and the final reflecting surface 51. Thus, the user 400 appears to have the first image of the display device 20 displayed at a display position that is farther (a few m in front of the viewpoint of the user 400, for example, 2m to 3m in front) than the final reflecting surface 51 in the direction in which the final reflecting surface 51 is viewed through the second reflecting mirror 40. That is, the user 400 appears to have the second image 300, i.e., a virtual image, based on the first image of the display device 20 displayed at a display position several m ahead of the automobile 100 (refer to fig. 3).
The display control section 22 controls the display state of the first image in the display device 20. The display control unit 22 communicates (wired communication or wireless communication) with the image pickup unit 90 via, for example, an in-vehicle network of the automobile 100. Image data of a captured image of the rear side of the automobile 100 is input from the imaging unit 90 to the display control unit 22. The display control section 22 displays a first image based on the captured image input from the imaging section 90 on the display device 20.
Here, the first image based on the captured image may be the captured image itself, an image obtained by image processing the captured image, or a CG (Computer Graphics) image created based on the captured image. For example, since the image captured by the image capturing unit 90 is dark at night, the image captured by the image capturing unit 90 can be subjected to brightness correction. Further, a CG image, a marker, or the like indicating an obstacle or the like captured in the image may be generated based on the image captured by the imaging unit 90, and the image obtained by superimposing the CG image, the marker, or the like on the captured image of the imaging unit 90 may be displayed on the display device 20. In addition, it is also possible to cause the display device 20 to display an image in which a mark indicating driving assistance information (for example, vehicle speed information, navigation information, pedestrian information, preceding vehicle information, lane departure information, vehicle condition information, or the like) is superimposed on an image captured by the imaging unit 90.
The display control unit 22 is constituted by, for example, a computer system having a processor and a memory as hardware. In other words, the display control unit 22 can be realized by a computer system having a processor and a memory, and the computer system functions as the display control unit 22 by the processor executing a program stored in the memory. The program may be recorded in advance in a memory of the computer system, may be provided through an electric communication line, or may be provided by being recorded in a non-transitory recording medium such as a memory card, an optical disk, or a hard disk drive that can be read by the computer system. A processor of a computer system is constituted by one or more electronic circuits including a semiconductor Integrated Circuit (IC) or a large scale integrated circuit (LSI). The term "integrated circuit" as used herein, such as an IC or an LSI, varies depending on the degree of Integration, and includes integrated circuits called a system LSI, a VLSI (Very Large Scale Integration), or an ULSI (Ultra Large Scale Integration). Furthermore, an FPGA (Field-Programmable Gate Array) programmed after LSI manufacture or a logic device capable of reconstructing a connection relationship within the LSI or reconstructing circuit division within the LSI can also be used as the processor. The plurality of electronic circuits may be integrated on one chip or may be distributed over a plurality of chips. The plurality of chips may be integrated into one device or may be distributed among a plurality of devices. A computer system as referred to herein includes a microcontroller having more than one processor and more than one memory. Thus, the microcontroller is also constituted by one or more electronic circuits including a semiconductor integrated circuit or a large-scale integrated circuit.
The imaging unit 90 is, for example, a CMOS (Complementary Metal Oxide Semiconductor) image sensor mounted at the rear of the automobile 100, and is used to image the rear of the automobile 100. The imaging unit 90 is not limited to a CMOS image sensor, and may be an image sensor such as a CCD (Charge Coupled Device) image sensor.
The image pickup unit 90 outputs image data obtained by picking up an image of the rear side of the automobile 100 to the display control unit 22 via, for example, an in-vehicle network. The imaging unit 90 is disposed at the center in the left-right direction of the rear portion of the automobile 100, and images a range that can be visually recognized by a conventional interior mirror, and the electronic mirror system 80 is used as a rear confirmation mirror like a conventional interior mirror. The imaging unit 90 may image the rear and lateral sides of the automobile 100. The imaging unit 90 may capture an image of a range that can be visually recognized by a conventional door mirror or wing mirror, or may use the electronic mirror system 80 as a rear confirmation mirror instead of the conventional door mirror or wing mirror. The imaging unit 90 is attached to the rear portion of the moving body 110 and to an upper portion of the moving body 110, but the attachment position of the imaging unit 90 is an example, and the imaging unit 90 may be attached to a position where a desired range can be imaged.
In the display system 10 of the present embodiment, the first image displayed by the display device 20, that is, the light (light forming the first image) output from the display device 20 is reflected a plurality of times (for example, three times in the present embodiment) by the first reflection surface 31, the second reflection surface 41, and the final reflection surface 51. Here, the distance (viewing distance) from the display position of the image (virtual image) visually recognized by the user 400 is determined based on the optical path length from the display screen 21 of the display device 20 to the final reflection surface 51, the focal distance of the optical system configured by the first reflection surface 31, the second reflection surface 41, and the final reflection surface 51, and the like. Thus, by reflecting the light output from the display device 20 a plurality of times, the apparent distance from the display position of the image can be kept at a desired distance, and the volume of the housing 70 (the housing chamber 73) can be reduced, and in particular, the length L1 from the second reflection surface 41 to the final reflection surface 51 can be shortened. Thus, the housing 70 can be miniaturized in the direction in which the user 400 views the final reflecting surface 51 through the second reflecting mirror 40, so that the miniaturized display system 10 can be realized.
(2.2) operation
Next, operations of the display system 10 of the present embodiment and the electronic mirror system 80 including the display system 10 will be described.
For example, when electric power is supplied from a battery of the automobile 100 to the Electronic mirror system 80 and a control signal for starting the operation is input to the Electronic mirror system 80 from an ECU (Electronic control unit) provided in the automobile 100, the Electronic mirror system 80 starts the operation.
For example, when a control signal is input from the ECU of the automobile 100 to the display control unit 22, the display control unit 22 causes the imaging unit 90 to image the rear of the automobile 100 at a predetermined frame rate, and acquires image data of the captured image from the imaging unit 90.
When image data of a captured image is input from the imaging section 90, the display control section 22 creates a first image based on the captured image and causes the display device 20 to display the first image.
When the first image is displayed in the display screen 21 of the display device 20, the light forming the first image is emitted toward the first reflection surface 31 in a direction parallel to the optical path a 11. The first reflective surface 31 reflects incident light from the display device 20 toward the second reflective surface 41. The second reflecting mirror 40 constituting the second reflecting surface 41 is a beam splitter, and the second reflecting surface 41 reflects a part of the incident light from the first reflecting surface 31 toward the final reflecting surface 51. The final reflection surface 51 is a concave mirror, and reflects light that forms a second image obtained by enlarging a first image displayed by the display device 20 toward the second reflection surface 41. When the reflected light reflected by the final reflecting surface 51 enters the second reflecting surface 41, a part of the reflected light from the final reflecting surface 51 passes through the final reflecting mirror 50 and is emitted to the outside of the housing 70, and therefore, the user 400 can view the second image enlarged by the final reflecting surface 51.
Here, the display device 20, the first reflecting surface 31, the second reflecting surface 41, and the final reflecting surface 51 are arranged around the range 200, the display device 20 and the first reflecting surface 31 face each other across the range 200, and the second reflecting surface 41 and the final reflecting surface 51 face each other across the range 200. Further, on the optical path before the light from the display screen 21 of the display device 20 reaches the final reflection surface 51, the optical path a11 of the exit light from the display device 20 intersects the optical path a13 of the reflected light from the second reflection surface 41. The second reflecting surface 41 and the final reflecting surface 51 are arranged such that an optical path a13 through which light propagates from the second reflecting surface 41 to the final reflecting surface 51 is substantially parallel to an optical path a14 through which light propagates from the final reflecting surface 51 to the second reflecting surface 41. Here, the optical path a13 may be "parallel" to the optical path a14, for example, substantially parallel when viewed from a direction perpendicular to the optical path a11 and the optical path a14, or the optical path a13 and the optical path a14 may intersect at an angle of about several degrees.
In the present embodiment, since the optical path a11 intersecting the optical path a13 is provided, the optical path length from the display screen 21 of the display device 20 to the point where the light reaches the final reflection surface 51 is the same, and the size of the display system 10 in the front-rear direction of the automobile 100 can be reduced.
Here, fig. 3 shows an example of an image displayed on the electron mirror system 80, and a second image (virtual image) 300 based on the first image is displayed on the outer surface 42 of the second reflecting mirror 40 formed of a beam splitter by light transmitted through the second reflecting mirror 40. The display system 10 displays the second image 300 obtained by reflecting the first image of the display device 20 with the first reflecting surface 31, the second reflecting surface 41, and the final reflecting surface 51, and thus recognizes the user 400 that the second image 300 is displayed, for example, several m ahead from the viewpoint of the user 400. Thus, the adjustment amount of the focus in the case where the user 400 views the second image 300 in a state where the user views the front of the automobile 100 through the windshield 102 becomes smaller than that in the case where the display device 20 is arranged several tens of cm in front of the user 400. Thereby, the adjustment time required for the user 400 to adjust the focus for the second image 300 displayed by the display system 10 can be shortened. In addition, it is easy to adjust the focus even in a case where the user 400 has difficulty in focusing at a close distance due to aging, hyperopia, or the like.
In the above-described embodiment, as shown in fig. 1, after the light emitted from the display device 20 is reflected by the first and second reflecting surfaces 31 and 41, the light is reflected by the final reflecting surface 51 toward the second reflecting surface 41, and the light is transmitted through the second reflecting mirror 40 and emitted to the outside. To form such light paths a11 to a14, the display device 20 emits light in a direction (light path a11 direction) inclined with respect to the normal direction DR1 (refer to fig. 1) of the display screen 21.
In addition, in the above-described embodiment, the second image 300 displayed by the display system 10 is an image based on the partial image P11 in the first image P1 displayed in the display screen 21 of the display device 20 (refer to fig. 4).
That is, in the display system 10 of the present embodiment, the first mirror 30, the second mirror 40, and the final mirror 50 constitute the reflection optical system B1, and the first mirror 30 reflects the partial image P11 that is a part of the first image P1 displayed on the display screen 21. Thus, the second image 300 formed by the light reflected by the reflection optical system B1 is a part of the virtual image 310 formed in the case where the reflection optical system B1 reflects the entire first image P1.
Here, in a state where the user 400, which is the driver of the automobile 100, is seated in a fixed position, the second image 300 visually recognized by both eyes of the user 400 is located at the center of the entire virtual image 310 in each of the up-down direction and the left-right direction. On the other hand, when the position of the head of the user 400 moves to the right side from the position shown in fig. 4, the second image 300R recognized by the binocular vision of the user 400 is an image of a range on the left side of the second image 300 in the entire virtual image 310. When the position of the head of the user 400 is shifted to the left, the second image 300L visually recognized by both eyes of the user 400 is an image of a range on the right side of the second image 300 in the entire virtual image 310.
As described above, in the present embodiment, when the head of the user 400 moves to the left or right, the range of the second image 300 visually recognized by the user 400 changes to the right or left in the entire virtual image 310. Likewise, when the head of the user 400 moves to the upper side or the lower side, the range of the second image 300 visually recognized by the user 400 varies to the lower side or the upper side in the entire virtual image 310. That is, when the head of the user 400 moves up, down, left, and right, the range of the second image 300 visually recognized by the user 400 changes according to the movement of the head of the user 400, and thus the presentation form of the second image 300 displayed by the display system 10 becomes a mirror-like presentation form.
(3) Modification example
The above-described embodiment is only one of various embodiments of the present disclosure. The above embodiment may be modified in various ways according to design and the like as long as the object of the present disclosure can be achieved.
Next, modifications of the above embodiment will be described. The modifications described below can be applied in appropriate combinations.
(3.1) modification 1
As shown in fig. 5 to 8, the display system 10 of modification 1 is different from the above-described embodiment in that the second reflective surface 601 having light transmissivity is formed by the surface of the polarizer 60. That is, in the display system 10 according to modification 1, at least one of the first reflecting surface 31 and the second reflecting surface 601 has a light-transmitting reflecting surface (in the present embodiment, the second reflecting surface 601) which is a surface of the polarizing element 60. Further, the display system 10 of modification 1 is also different from the above-described embodiment in that optical elements 61, 62 that impart a phase difference of a quarter wavelength in the electric field vibration direction of incident light are provided on the surface of the display screen 21 of the display device 20 and the surface of the polarizing element 60, respectively. Here, the optical elements 61 and 62 giving a phase difference to incident light means that a phase difference of a quarter wavelength is generated between light incident on the optical elements 61 and 62 and light transmitted through the optical elements 61 and 62 by advancing or retarding the phase of light incident on the optical elements 61 and 62. Note that the configuration of the display system 10 other than the polarizing element 60 and the optical elements 61 and 62 is the same as that of the above-described embodiment, and the same reference numerals are given to the common configuration and the description thereof is omitted.
In fig. 5, light paths a21 to a24 before light emitted from the vicinity of the center of the display screen 21 of the display device 20 is reflected by the final reflection surface 51 and output to the outside of the display device 20 are shown by broken lines. In fig. 5, lines indicating the light passing range 200, the light paths a21 to a24 of the light passing through the range 200, the length L1, and the like are illustrated for explanation only and are not actually shown.
The polarizing element 60 is constituted by, for example, a wire grid polarizer. The polarizing element 60 is, for example, a reflective polarizing film, and is provided on the surface of the substrate 40A (the surface on the side of the housing chamber 73) attached to the opening 71 of the case 70. In other words, the second optical member having the second reflecting surface 601, that is, the light transmissive optical member 40 having light transmissivity is configured by the substrate 40A and the polarizing element 60. Further, the light-transmissive optical member 40 includes a substrate 40A and a polarizing element 60 provided on a surface of the substrate 40A. The substrate 40A is, for example, a transparent plate having light transmissivity, and is a glass plate or a plate made of synthetic resin (e.g., acrylic resin or polycarbonate resin). The polarizing element 60 is, for example, a polarizing plate in which a fine wire mesh of a nanometer order is formed on a synthetic resin substrate, and polarizes light by transmitting light in a specific polarization state. For example, the polarizer 60 is configured to transmit P-polarized light and reflect S-polarized light. The polarizing element 60 is not limited to the wire grid polarizer, and may be any optical element as long as it transmits light in a specific polarization state to polarize the light.
The display device 20 of the present embodiment includes, for example, a liquid crystal display including a liquid crystal panel in which liquid crystal is sandwiched between two polarizing plates, and thus the light C1 (see fig. 6) emitted from the display device 20 is light in a predetermined polarization state. In this embodiment, a case where the light C1 emitted from the display device 20 is P-polarized light will be described as an example. In fig. 6, the polarizing element 60 and the optical element 62 are disposed with a space therebetween for convenience of explanation, but actually, the polarizing element 60 and the optical element 62 are disposed in a state of being closely bonded by an adhesive. That is, the polarizing element 60 and the optical element 62 are provided so as to be laminated on the surface of the substrate 40A. Further, the substrate 40A and the polarizing element 60 may be disposed in a state of being closely bonded by adhesion.
The optical elements 61, 62 respectively provided on the surfaces of the display screen 21 and the polarizing element 60 of the display device 20 are phase difference plates formed of birefringent materials whose traveling speeds of light differ according to the vibration direction of the light. In the present embodiment, the optical elements 61 and 62 are 1/4 wavelength plates that impart a quarter-wavelength phase difference between the P-polarized component and the S-polarized component.
Fig. 7 is a schematic diagram for explaining a case where the optical element 62 provided on the surface of the polarizing element 60 imparts a phase difference to incident light. In fig. 7, the optical path of light incident on the surface of the optical element 62 before the light is reflected by the surface of the polarizing element 60 and exits from the surface of the optical element 62 is shown by a broken line. Light incident on the surface of the optical element 62 at the incident angle θ 1 is refracted at the surface of the optical element 62. Here, when the refraction angle is θ 2, the thickness of the optical element 62 is t1, and the optical path length traveled by the light incident on the surface of the optical element 62 before reaching the surface of the polarizing element 60 (the second reflection surface 601) is L2, the relationship of the following expression (1) is established.
L2×cosθ2＝t1…(1)
Therefore, if the thickness t1 and the refraction angle θ 2 are designed so that the phase difference generated by the optical path length L2 is equal to a quarter of the wavelength of the light incident on the optical element 62, the polarization state of the incident light can be converted from circularly polarized light to linearly polarized light by the optical element 62. Further, if the optical element 61 is configured similarly to the optical element 62, the polarization state of the incident light can be converted from linearly polarized light to circularly polarized light by the optical element 61.
The optical element 62 is preferably an optical element satisfying the formula (1), but is not limited thereto, and an optical element having a characteristic that the phase difference is one-quarter of the wavelength of light when the incident angle θ 1 is 0 ° may be used.
In addition, as the optical elements 61 and 62, it is preferable to use optical elements having wide bandwidth characteristics in which the phase difference is a value close to one quarter of the wavelength of light in the entire range of the visible light bandwidth. By using an optical element having a wide bandwidth characteristic, the efficiency can be further improved, and the coloring of an image can be suppressed.
Further, although an adhesive is provided in advance on the polarizing element 60 and the optical element 62, the present invention is not limited to this configuration, and the polarizing element and the optical element may be bonded together using an adhesive without providing an adhesive. When an adhesive having a lower viscosity than the adhesive is used, variations in the thickness of the optical element 62 itself, variations in the thickness of the adhesive layer between the substrate 40A and the polarizing element 60, and variations in the thickness of the adhesive layer between the polarizing element 60 and the optical element 62 can be reduced. This can suppress minute undulations in the interfaces of the substrate 40A, the polarizing element 60, and the optical element 62. Therefore, the image quality of the reflected image can be suppressed from deteriorating. The adhesive is, for example, a UV-curable adhesive.
In the present embodiment, the polarizing element 60 and the optical element 62 are provided in a stacked manner on the surface of the substrate 40A, but another light-transmitting substrate may be provided on the surface of the optical element 62 provided on the surface of the polarizing element 60 on the side where the polarizing element 60 is not provided. Specifically, as shown in fig. 8, a substrate 40B is further laminated on the surface of the optical element 62 opposite to the polarizing element 60. In other words, the polarizing element 60 and the optical element 62 are sandwiched between the substrates 40A and 40B. That is, the light-transmissive optical member 40 further includes a pair of light- transmissive substrates 40A and 40B sandwiching the polarizing element 60 and the optical element 62 provided on the surface of the polarizing element 60 from both sides. This can further reduce the thickness variation of the optical element 62 itself, the thickness variation of the adhesive between the substrate 40A and the polarizing element 60, and the thickness variation of the adhesive between the polarizing element 60 and the optical element 62. This can suppress minute undulations in the interfaces between the substrates 40A and 40B, the polarizing element 60, and the optical element 62, and thus can suppress the degradation of the image quality of the reflected image. In the sandwich structure shown in fig. 8, an adhesive for bonding may be used instead of the adhesive.
Here, a case before light emitted from the display device 20 is output to the outside of the display system 10 will be described based on fig. 6. Fig. 6 is a schematic diagram for explaining the polarization performed in the optical elements 61 and 62. In fig. 6, the display screen 21 of the display device 20 is illustrated separately from the optical element 61, and the polarizing element 60 is illustrated separately from the optical element 62, but in the present modification, the optical element 61 is provided on the display screen 21 of the display device 20, and the optical element 62 is provided on the polarizing element 60. Further, in the present modification, a gap may be provided between the display screen 21 of the display device 20 and the optical element 61, or a gap may be provided between the polarizing element 60 and the optical element 62.
For example, when P-polarized light C1 is emitted from the display device 20, the P-polarized light C1 is transmitted through the optical element 61 and converted into circularly polarized light C2, and therefore the light C3 reflected by the first reflection surface 31 is also circularly polarized light. When the light C3 reflected by the first reflecting surface 31 passes through the optical element 62, the circularly polarized light C3 is converted into S-polarized light C4 and enters the second reflecting surface 601 of the polarizer 60. Since the polarizer 60 transmits only P-polarized light and reflects S-polarized light, the light C4 incident on the second reflection surface 601 of the polarizer 60 is reflected by the second reflection surface 601 of the polarizer 60. The light C5 reflected by the second reflecting surface 601 of the polarizer 60 is converted into the circularly polarized light C6 by the optical element 62, and then reflected by the final reflecting surface 51 to be incident on the optical element 62 again. The light C7 reflected by the final reflection surface 51 is circularly polarized light, and the light C7 passes through the optical element 62, whereby the circularly polarized light C7 is converted into P-polarized light C8, which is incident on the second reflection surface 601 of the polarizer 60. Since the polarizer 60 is configured to transmit only P-polarized light, the light C8 incident on the second reflection surface 601 after passing through the optical element 62 passes through the polarizer 60, passes through the substrate 40A, and is emitted to the outside. Thus, the user 400 can view the second image 300 displayed on the final reflection surface 51 of the final mirror 50 using the light C9 emitted to the outside after passing through the polarizing element 60 and the substrate 40A.
In modification 1, a second optical member having a second reflection surface 601 is realized by the substrate 40A and the polarizing element 60. Since the second reflecting surface 601 is formed by the surface of the polarizer 60, substantially all of the reflected light (S-polarized light) from the first reflecting surface 31 is reflected toward the final reflecting surface 51, and substantially all of the reflected light (P-polarized light) from the final reflecting surface 51 can be transmitted. Therefore, compared to the above-described embodiment in which the second reflection surface is formed by the surface of the half mirror, the loss of light can be reduced, and the luminance of the second image 300 displayed by the display system 10 can be increased. In addition, the brightness of the second image 300 is only required to be the same as that of the above-described embodiment in which the second reflection surface is constituted by the surface of the half mirror, and the power consumption of the display device 20 can be reduced by reducing the loss of light.
As shown in fig. 9, when unpolarized external light C11 (light reflected by the face of the user 400 or the interior member of the automobile 100, light reflected by a structure outside the vehicle cabin, or light such as sunlight) enters from the direction of the user 400 viewing the display system 10, the external light C11 is converted into P-polarized light C12 by the polarizer 60. The light C12 is converted into circularly polarized light C13 by the optical element 62, and is reflected by the final reflection surface 51. The light C14 reflected by the final reflection surface 51 is converted into S-polarized light C15 by the optical element 62, but the S-polarized light C15 is reflected by the polarizing element 60, so that the light C16 reflected toward the user 400 can be greatly suppressed. Thus, the contrast of the second image 300 displayed by the display system 10 is improved. Further, since it is possible to suppress glare light such as sunlight and lamp light of a following vehicle from being reflected toward the user 400, the possibility that the user 400 feels glare can be reduced. The polarizing element 60 of the present modification is a reflective polarizing film, and there is almost no reflected light (return light). Therefore, compared to a vapor deposition type half mirror in which about 25% of return light is generated by reflection, the contrast of the second image 300 displayed by the display system 10 is further improved because the reflection light of the external light is reduced.
Although the light C16 reflected toward the user 400 is greatly reduced, there is a possibility that a very strong light such as sunlight is condensed by the action of the concave mirror of the final reflection surface 51 and is emitted. In order to suppress such outgoing light generated by the convergence, in the display system 10 of modification 1, a resin film having a lower transmittance than that of the substrate 40A may be attached to the outer surface (the surface closer to the user 400) of the substrate 40A. Instead of attaching a resin film having a low transmittance to the substrate 40A, the substrate 40A itself may be made of glass or a resin plate having a low transmittance such as a glass frit. Further, in the case where a resin film having a lower transmittance than the substrate 40A is attached to the outer surface of the substrate 40A, or in the case where the transmittance of the substrate 40A itself is reduced, the second image 300 based on the first image displayed by the display device 20 becomes dark, and therefore it is preferable to increase the luminance of the display device 20.
The substrate 40A may be a half mirror, and the substrate 40A including the half mirror can be used as a mirror by adding a mechanism for changing an angle at which the display system 10 is arranged in a state where the display system 10 does not display an image.
(3.2) modification 2
As shown in fig. 10, the display system 10 of modification 2 is different from that of modification 1 in that it further includes a phase control member 63. Note that the configuration other than the phase control member 63 is the same as that of the above-described embodiment or modification 1, and therefore the same reference numerals are given to the common components and the description thereof is omitted.
In the display system 10 according to modification 2, the optical element 62 is disposed on the surface of the polarizing element 60 on which the light from the display device 20 is incident. A phase control member 63 that imparts a phase difference of a quarter wavelength in the direction of vibration of an electric field of incident light is disposed on the surface of the light-transmissive optical member (e.g., the substrate 40A) that is located outside the display system 10.
As described in "(3.1) modification 1", in the display system 10 of modification 1, the light C8 incident on the substrate 40A after passing through the optical element 62 is P-polarized light. Thus, the P-polarized light C8 passes through the phase control member 63, whereby the light C10 output to the outside of the display system 10 becomes circularly polarized light. Thereby, even in a case where the user 400 wears polarized glasses, the possibility that the second image displayed by the display system 10 appears dark can be reduced.
In modification 2, the phase control member 63 is a phase control member that provides a quarter-wave phase difference, but may be a phase control member that provides a phase shifted by a quarter-wave (for example, a phase difference between one fifth and three tenth of a wavelength). This can suppress coloring of the image.
(3.3) modification 3
As shown in fig. 11A, the display system 10 of modification 3 differs from the above-described embodiment and modifications 1 and 2 in that the final reflection surface 51 reflects light in a direction different from the direction in which light enters from the second reflection surface 41. Note that the same reference numerals are given to common constituent elements and the description thereof is omitted, except that the final reflection surface 51 reflects light in a direction different from the direction in which light enters from the second reflection surface 41, as in the above-described embodiments or modifications 1 and 2.
Fig. 11B shows the configuration of the reflective optical system B1 described in the above-described embodiment. Here, in the reflection optical system B1 of modification 3 shown in fig. 11A and the reflection optical system B1 of the above-described embodiment shown in fig. 11B, the exit angle of the display device 20 is set to about 16 degrees, the reflection angle of the first reflection surface 31 is set to about 22 degrees, and the reflection angle of the second reflection surface 41 is set to about 30 degrees. In the reflection optical system B1 shown in fig. 11B, the reflection angle of the final reflection surface 51 is set to 0 degree, whereas in the present modification, the reflection angle of the final reflection surface 51 is set to about 4 degrees by adjusting only the orientation of the final mirror 50. That is, in the present modification, the final reflecting surface 51 reflects light in a direction different from the direction in which light enters from the second reflecting surface 41 by changing the direction of the final reflecting mirror 50.
In the case where the display device 20 emits light in a direction inclined with respect to the normal direction DR1 of the display screen 21, when the reflection angle of the final reflection surface 51 is 0 degree, keystone distortion occurs in the second image 300B displayed by the display system 10 as shown in fig. 12B. In the case where the display system 10 is used for the electronic mirror system 80 of the automobile 100, if distortion correction of the second image 300B is not performed, the inclination of an object (a utility pole, a guardrail, or the like) displayed at the left and right ends of the second image 300B is conspicuous, and the user 400 may feel unnatural. In addition, when the distortion correction of the second image 300B is performed, the image on the bottom side of the second image 300B is easily distorted.
In contrast, in modification 3, the final reflecting surface 51 reflects light in a direction different from the incident light direction, and as shown in fig. 12A, the second image 300A displayed on the display system 10 is an image in which the entire image is slightly curved, but trapezoidal distortion can be suppressed. Thus, even without performing distortion correction of the second image 300A, the tilt of the object displayed at the left and right ends of the second image 300A does not easily become conspicuous. In addition, even in the case where the distortion correction of the second image 300A is performed, the image of the second image 300A is not easily distorted.
(3.4) modification 4
As shown in fig. 13, the display system 10 of modification 4 is different from the above-described embodiment in that it further includes a video reducing member. The image reducing member reduces an image that is generated mainly on the inner surface (second reflecting surface 41) of the translucent optical member (second reflecting mirror 40) of light (light indicated by a light path a41 in fig. 13) incident from the outside of the display system 10. In modification 4, the image reducing member includes a reflection reducing member 75 and a half mirror 76 formed on an inner surface (second reflecting surface 41) of the translucent optical member (second reflecting mirror 40). Since the configuration other than the image reducing member is the same as that of the above-described embodiment, the same reference numerals are given to the common components, and the description thereof is omitted.
In modification 4, a half mirror 76 having a light transmittance and a light reflectance of about 50% is formed on the inner surface of the second reflecting mirror 40 as the translucent optical member, for example. The translucent optical member (second reflecting mirror 40) is a flat surface. This enables the half mirror 76 to be formed uniformly and with high accuracy on the inner surface of the second mirror 40. Here, the inner surface (second reflecting surface 41) of the second reflecting mirror 40 (light transmitting member) refers to a surface on the inner side of the case 70A out of two side surfaces of the second reflecting mirror 40 in the direction in which the light from the inside of the case 70A transmits the second reflecting mirror 40. The second reflecting mirror 40 is arranged such that the second reflecting mirror 40 obliquely intersects with the output direction of the light reflected by the final reflecting surface 51 (the direction parallel to the arrow DR2 in fig. 13). That is, the second reflecting mirror 40 is disposed such that the output direction of the light reflected by the final reflecting surface 51 intersects the normal direction DR3 of the inner surface of the second reflecting mirror 40 at a predetermined angle θ 41 smaller than 90 degrees. Accordingly, when the inner surface of the second reflecting mirror 40 is viewed from the image output direction, the reflection of light on the inner surface (second reflecting surface 41) is reduced, and thus the contrast of the second image 300 viewable through the inner surface can be improved. That is, in the present modification, the image reducing member includes the second reflecting mirror 40 (translucent optical member), and the second reflecting mirror 40 is disposed so that the second reflecting mirror 40 intersects the output direction of the light reflected by the final reflecting surface 51 obliquely.
The display system 10 according to modification 4 includes a protruding portion 74 protruding rearward from the upper portion of the housing 70A, and a reflection reducing member 75 is disposed below the protruding portion 74. That is, the reflection reducing member 75 is disposed at a portion of the protruding portion 74 that faces the outer surface 42 of the second reflecting mirror 40.
The reflection reducing member 75 is disposed in a direction in which light (light indicated by an optical path a41 in fig. 13) incident on the inner surface of the second reflecting mirror 40 in the image output direction (a direction parallel to an arrow DR2 in fig. 13, that is, a direction opposite to the image output direction) from the outside of the housing 70 is reflected by the inner surface (the second reflecting surface 41) of the second reflecting mirror 40, and the reflection reducing member 75 faces the second reflecting mirror 40 as the translucent optical member. Here, most of the reflection reducing member 75 is a flat plate shape, and the dimension of the reflection reducing member 75 in the left-right direction is the same as the dimension of the second reflecting mirror 40 in the left-right direction or is larger than the dimension of the second reflecting mirror 40 in the left-right direction. The reflection reducing member 75 has a function of absorbing incident light. The color of the reflection reducing member 75 is darker than the inner surface of the ceiling portion 101 of the moving body main body 110 (see fig. 2), and is, for example, black. The reflection reducing member 75 has a function of absorbing light, but may have a function of scattering light.
As described above, in the present modification, the image reducing member includes the reflection reducing member 75, and the reflection reducing member 75 is disposed in a direction in which light incident on the inner surface of the second reflecting mirror 40 (translucent optical member) from the outside of the display system 10 in the output direction of the light reflected by the final reflecting surface 51 is reflected by the inner surface, and faces the outer surface 42 of the second reflecting mirror 40 (translucent optical member). The reflection reducing member 75 absorbs or scatters light. Accordingly, the amount of light incident on the inner surface of the second reflecting mirror 40 is reduced because the light incident on the second reflecting mirror 40 from the region where the reflection reducing member 75 is arranged is reduced. Thus, there are the following advantages: the contrast of the second image 300 formed by the light transmitted through the second reflecting mirror 40 becomes high, and the second image 300 displayed by the display system 10 is easily viewed.
In the present modification, the image reducing member includes both the half mirror 76 and the reflection reducing member 75 formed on the translucent optical member, but may include only either the half mirror 76 or the reflection reducing member 75. For example, instead of the protrusion 74, a cloth-like material having a light absorbing function or a light scattering function corresponding to the reflection reducing member 75 may be formed on the ceiling portion 101.
(3.5) modification 5
As shown in fig. 14, the display system 10 according to modification 5 further includes a light control member 23, and the light control member 23 is disposed on the display screen 21 of the display device 20 and controls an output angle of light emitted from the display device 20. Since the configuration other than the light control member 23 is the same as that of the above-described embodiment, the same reference numerals are given to the common components, and the description thereof is omitted.
The light control member 23 limits the exit angle of the light emitted from the display device 20 within a prescribed allowable angle range. That is, the light control member 23 limits the exit angle so that light does not exit the display device 20 at an exit angle outside the prescribed allowable angle range.
In fig. 14, a line of sight of the user 400 in a case where the second mirror 40 of the display system 10 is viewed from the upper side where the image range (japanese: アイボックス)410 is visible is illustrated with a broken line a 31. The visible image range 410 is a range in which the edge of the second image as a virtual image is not visible when the viewpoint is moved in the vertical, horizontal, and vertical directions. Here, light entering from the direction of the line of sight shown by the broken line a31 enters the display device 20 after being reflected by the first mirror 30 and the final mirror 50. The light control member 23 sets the allowable angle range so that the angle θ 31 of the incident light C31 to the surface of the light control member 23 is an angle outside the allowable angle range in which the light control member 23 restricts the output angle. Thus, in the case where the user 400 observes the second mirror 40 of the display system 10 from the upper side where the image range 410 is visible, it is not easy to view the reflected image reflected by the first mirror 30 and the final mirror 50 in the display screen 21 of the display device 20.
In addition, in fig. 14, a line of sight of the user 400 in a case where the second mirror 40 of the display system 10 is viewed from the lower side where the image range 410 is visible is illustrated with a broken line a 32. Here, the allowable angle range of the light control member 23 for the output angle limitation is set so that the angle θ 32 at which the light C32 incident from the direction of the line of sight shown by the broken line a32 enters the surface of the light control member 23 is an angle outside the allowable angle range of the light control member 23. Thus, in the case where the user 400 observes the second reflecting mirror 40 of the display system 10 from the lower side where the image range 410 is visible, it is not easy to directly view the display screen 21 of the display device 20.
(3.6) modification 6
In the above embodiment and modifications 1 and 2, the second optical member provided with the second reflecting surfaces 41 and 601 has light transmissivity, but the first optical member (the first reflecting mirror 30) provided with the first reflecting surface 31 may have light transmissivity. That is, at least one of the first optical member having the first reflecting surface 31 and the second optical member having the second reflecting surfaces 41 and 601 may have light transmissivity for transmitting a part of the incident light. The reflected light from the final reflecting surface 51 is transmitted through the light-transmissive optical member having light transmissivity of the first optical member and the second optical member, and is emitted to the outside of the display system 10.
As shown in fig. 15, when the final reflecting surface 51 reflects light toward the first reflecting surface 31, the first reflecting mirror 30 including the first reflecting surface 31 may be light-transmissive, and a part of the reflected light from the final reflecting surface 51 may be transmitted through the first reflecting mirror 30 and emitted to the outside of the display system 10. In the display system 10 shown in fig. 15, since the optical path a11 and the optical path a13 also intersect with each other, the length between the first reflecting surface 31 and the final reflecting surface 51 can be reduced as compared with the case where the optical paths a11 and a13 do not intersect with each other, and the display system 10 can be downsized.
Here, the first reflecting surface 31 having light permeability of the first reflecting surface 31 and the second reflecting surface 41 may be formed by a surface of a beam splitter, for example. The reflected light from the final reflection surface 51 passes through the first mirror 30 formed of a beam splitter and is emitted to the outside of the display system 10. Here, the second reflecting mirror 40 provided with the second reflecting surface 41 may have no light permeability or light permeability.
In the display system 10 shown in fig. 15, as in modification 1, the first reflecting mirror 30 having optical transparency may be configured by a polarizing element, and the first reflecting surface 31 of the first reflecting mirror 30 may be configured by a surface of the polarizing element. In this case, an optical element as a phase difference plate that imparts a phase difference of a quarter wavelength in the electric field vibration direction of incident light is provided on the surface of the polarizing element and the surface of the display screen 21 of the display device 20. Thereby, the polarization state of light can be converted by the optical element provided on the display screen 21 of the display device 20 and the optical element provided on the surface of the polarizing element, respectively. Thus, in the display system 10, the light emitted from the display screen 21 of the display device 20 is reflected by the first reflecting surface 31, and the reflected light reflected by the final reflecting surface 51 can be transmitted through the first reflecting mirror 30 having the first reflecting surface 31 and emitted to the outside of the display system 10.
(3.7) other modifications
In the above-described embodiment, the reflective optical system that reflects the light emitted from the display device 20 includes the first reflective surface 31, the second reflective surface 41, and the final reflective surface 51, but the arrangement of the display device 20, the first reflective surface 31, the second reflective surface 41, and the final reflective surface 51 is not limited to the above-described embodiment. For example, the display device 20 may be disposed in an upper portion of the storage chamber 73 with the display screen 21 facing downward, and the first reflecting mirror 30 may be disposed in a lower portion of the storage chamber 73 with the first reflecting surface 31 facing upward. The display system 10 may include the first reflecting surface 31 and the second reflecting surface 41 between the time when light reaches the final reflecting surface 51 from the display device 20, or may include one or more reflecting surfaces other than the first reflecting surface 31 and the second reflecting surface 41.
In the display system 10 of the above embodiment, the final reflection surface 51 is disposed so that the reflection angle of the light incident along the optical paths a13 and a23 becomes 0 degree, but the reflection angle of the light incident along the optical paths a13 and a23 is not limited to 0 degree, and can be changed as appropriate depending on the optical path design.
In the display system 10 according to the above-described embodiment and modifications 1 and 2, the light reflected from the final reflecting surface 51 may be transmitted through a member having light transmittance (for example, a light-transmitting cover provided in the housing 70) other than the first reflecting mirror 30 and the second reflecting mirror 40 and then emitted to the outside of the display system 10.
In the display system 10 of the above embodiment, the first reflection surface 31 and the second reflection surface 41 are each a flat surface, but at least a part of the first reflection surface 31 and the second reflection surface 41 may be a curved surface. By forming at least a part of the first reflection surface 31 and the second reflection surface 41 as a curved surface, the surfaces of the first reflection surface 31 and the second reflection surface 41 can be designed so that distortion of an image can be reduced and resolution can be improved.
In the display system 10 of the above-described embodiment (except for modification 6), the second reflecting surface 41 is a surface having a light-transmissive optical member (second reflecting mirror 40) that transmits a part of incident light, and the reflected light from the final reflecting surface 51 is transmitted through the second reflecting mirror 40 and is emitted to the outside of the display system 10. In this case, it is preferable that the length in the longitudinal direction of the display device 20 is shorter than the length in the longitudinal direction of the second reflecting surface 41 of the second mirror 40 as the second optical member and the final reflecting surface 51 of the final mirror 50 as the final optical member. Similarly, the length of the first reflecting surface 31 of the first reflecting mirror 30 as the first optical member in the longitudinal direction is preferably shorter than the length of the second reflecting surface 41 of the second reflecting mirror 40 as the second optical member and the length of the final reflecting surface 51 of the final reflecting mirror 50 as the final optical member in the longitudinal direction. Here, the longitudinal direction is a direction corresponding to the longitudinal direction of the second image 300 displayed by the display system 10, is an arrangement direction of the left and right eyes of the user viewing the second image 300, and is a direction corresponding to the width direction of the automobile 100 when the display system 10 is applied to the electronic mirror system 80 of the automobile 100. Specifically, for example, the length in the long side direction of the display device 20 is about seventy percent of the length in the long side direction of the final reflection surface 51, and the length in the long side direction of the first reflection surface 31 is about eighty percent of the length in the long side direction of the final reflection surface 51. The second reflecting surface 41 and the final reflecting surface 51 have the same length in the longitudinal direction. In addition, the term "equal" in the present disclosure is defined to mean equal to each other within an error range of about several% (for example, about 1%) in addition to the case of strict coincidence. That is, the length of the second reflecting surface 41 in the longitudinal direction may not only completely match the length of the final reflecting surface 51 in the longitudinal direction, but may also be within an error range of about several% (about 1%, for example) with respect to the length of the second reflecting surface 41 or the final reflecting surface 51 in the longitudinal direction. However, it is preferable that the length of the second reflecting surface 41 in the longitudinal direction is within the above error range and is configured to be longer than the length of the final reflecting surface 51 in the longitudinal direction. Thereby, as shown in fig. 16, R-shapes can be provided at the four corners of the second mirror 40 and the final mirror 50. As a result, as shown in fig. 3, when the display system 10 mounted on the automobile 100 is viewed from the front, the housing 70 can be provided with an R shape at the four corners, and can be downsized. In addition, since the housing 70 has an R shape at four corners, a feeling of pressure when the display system 10 is viewed from the passenger seat side can be reduced.
Further, it is more preferable that the length in the longitudinal direction of the display device 20 is shorter than the length in the longitudinal direction of the first reflection surface 31, and the length in the longitudinal direction of the second reflection surface 41 is equal to the length in the longitudinal direction of the final reflection surface 51. Thereby, the R shape can be set larger at the four corners of the second mirror 40 and the final mirror 50, and therefore, further miniaturization can be achieved.
In the display system 10 of the above-described embodiment and modification, the display device 20 is a liquid crystal display device including a liquid crystal panel and a Light source device, but the display device 20 may be a self-Light-Emitting display panel including an OLED (Organic Light Emitting Diode) or the like. In addition, the display device 20 may also be of the following structure: an image is drawn on a screen by scanning a laser beam across the screen from behind the diffusion transmission type screen. In addition, the display device 20 may be configured to project an image on a screen by a projector from behind the diffusion transmission type screen.
The Display system 10 of the above-described embodiment and the modification is applied to the electronic mirror system 80, but the Display system 10 may also be applied to a Head-Up Display (HUD) used for the automobile 100 as a mobile body. That is, in the head-up display including the display system 10, the display system 10 projects an image from below the windshield 102 (reflective member) of the automobile 100 to the windshield 102, and the user 400 (driver) visually recognizes the image reflected by the windshield 102. In such a head-up display, the user 400 visually recognizes that an image (virtual image) is projected in a space in front of (outside) the automobile 100.
The display system 10 according to the above-described embodiment and modification is not limited to the configuration in which the captured image of the rear of the automobile 100 is displayed, and may display an image based on the captured image of the lateral rear, lateral side, or front side of the automobile 100, for example.
The electronic mirror system 80 including the display system 10 of the above-described embodiment and modification is not limited to being applied to the automobile 100, and may be applied to a mobile body other than the automobile 100, such as a two-wheeled vehicle, a train, an airplane, a construction machine, and a ship.
The display system 10 is not limited to one device, and may be configured by a plurality of devices. That is, the functions of the display system 10 may be provided to two or more devices in a distributed manner. The display control unit 22 may be provided in an ECU of the automobile 100 or a server device outside the automobile 100, and in this case, the image displayed by the display device 20 is created by the ECU or the server device.
(conclusion)
As described above, the display system (10) according to the first aspect displays the second image based on the first image displayed by the display device (20). The display system (10) has at least a first reflection surface (31) and a second reflection surface (41, 601) on optical paths (A11, A21, A13, A23) between the display device (20) and a final reflection surface (51) that reflects light emitted from the display device (20) toward the outside of the display system (10). The first reflecting surface (31) reflects light emitted from the display device (20) toward the second reflecting surface (41, 601). The second reflecting surface (41, 601) reflects the light reflected from the first reflecting surface (31) toward the final reflecting surface (51). Before light emitted from a display device (20) reaches a final reflection surface (51), first optical paths (A11, A21) for propagating light from a display screen (21) of the display device (20) to a first reflection surface (31) intersect second optical paths (A13, A23) for propagating light from second reflection surfaces (41, 601) to the final reflection surface (51).
According to this embodiment, since the optical paths (a11, a21) intersect the optical paths (a13, a23), the display system (10) can be reduced in size compared to a case where the optical paths (a11, a21) do not intersect the optical paths (a13, a 23).
A display system (10) according to a second aspect is a display system (10) that displays a second image that is based on a first image displayed by a display device (20). A display system (10) is provided with a display device (20), a first optical member (30), a second optical member (40), and a final optical member (50). The first optical member (30) is disposed so as to face the display device (20), and the first optical member (30) has a first reflecting surface (31) that reflects first incident light that enters from a display screen (21) of the display device (20) in a first direction in a second direction that is different from the first direction. The second optical member (40) is disposed so as to face the first reflecting surface (31), and has a second reflecting surface (41, 601) that reflects second incident light that enters from the first reflecting surface (31) in the second direction, in a third direction that is different from the second direction. The final optical member (50) is disposed so as to face the second reflecting surfaces (41, 601), and has a final reflecting surface (51) that reflects third incident light that enters the final optical member in the third direction from the second reflecting surfaces (41, 601). The optical paths (A11, A21) of the first incident light intersect the optical paths (A13, A23) of the third incident light.
According to this embodiment, since the optical paths (a11, a21) intersect the optical paths (a13, a23), the display system (10) can be reduced in size compared to a case where the optical paths (a11, a21) do not intersect the optical paths (a13, a 23).
In a display system (10) according to a third aspect, in the first aspect, light on a first optical path (A11, A21) is emitted in a direction inclined with respect to the normal direction of a display screen (21).
According to this mode, the display system (10) can be miniaturized.
In a display system (10) according to a fourth aspect, in the third aspect, the final reflection surface (51) reflects light in a direction different from the direction in which light is incident from the second reflection surface (41, 601).
According to this aspect, keystone distortion of the second image can be reduced.
In a display system (10) according to a fifth aspect, in the second aspect, the first incident light is emitted in a direction inclined with respect to a normal direction of the display screen (21). The final reflection surface (51) reflects the third incident light in a fourth direction that is different from the third direction in which the third incident light is incident from the second reflection surface (41, 601).
According to this aspect, the display system (10) can be miniaturized, and keystone distortion of the second image can be reduced.
In a display system (10) according to a sixth aspect, in any one of the first to fifth aspects, at least one of the first reflecting surface (31) and the second reflecting surface (41, 601) is a surface of a light-transmissive optical member (30, 40) having light transmissivity for transmitting a part of incident light. The light reflected from the final reflection surface (51) is transmitted through the translucent optical members (30, 40) and emitted to the outside of the display system (10).
According to this mode, the display system (10) can be miniaturized.
In a display system (10) according to a seventh aspect, in the sixth aspect, the light-transmissive optical members (30, 40) include beam splitters.
According to this aspect, the beam splitter can realize a function of reflecting light and a function of emitting reflected light from the final reflection surface (51) to the outside of the display system (10).
In a display system (10) according to an eighth aspect, in the sixth aspect, the light-transmissive optical members (30, 40) include a substrate (40A) and a polarizing element (60). And optical elements (61, 62) that have a phase difference of a quarter wavelength in the direction of vibration of the electric field of incident light on the surfaces of the display screen (21) and the polarizing element (60).
According to this embodiment, the function of reflecting light and the function of emitting the reflected light from the final reflection surface (51) to the outside of the display system (10) can be realized by the polarizing element (60), and the loss of light can be reduced. A phase difference can also be given to incident light that enters the surface of the polarizing element (60) through the optical elements (61, 62). Thus, the polarizing element (60) can reflect incident light from the display device (20) or the first reflection surface (31) and transmit reflected light from the final reflection surface (51).
In a display system (10) according to a ninth aspect, in the eighth aspect, the light-transmissive optical member (40) further includes another light-transmissive substrate (40B), and the polarizing element (60) and the optical element (62) provided on the surface of the polarizing element (60) are sandwiched between the light-transmissive substrate (40B) and the substrate (40A).
According to this embodiment, by sandwiching the polarizing element (60) and the optical element (62) from both sides by the two substrates (40A, 40B), it is possible to reduce the thickness variation of the optical element (62) itself, the thickness variation between the substrate (40A) and the polarizing element (60), and the thickness variation between the polarizing element (60) and the optical element (62). Therefore, the minute undulation at each interface of the polarizing element (60), the optical element (62), and the two substrates (40A, 40B) can be suppressed, and therefore the deterioration of the image quality of the reflected image can be suppressed.
In a display system (10) according to a tenth aspect, in the eighth aspect, a phase control member (63) is further provided, and the phase control member (63) gives a phase difference of a quarter wavelength in an electric field vibration direction of incident light. In the polarizing element (60), an optical element (62) is disposed on a surface (601) on which light from the display device (20) is incident. The phase control member (63) is disposed on the surface of the light-transmitting optical component (40A) that is on the outer side of the display system (10).
According to this embodiment, light output from the inside of the display system 10 to the outside after passing through the phase control member (63) can be converted from linearly polarized light to circularly polarized light. Thus, even when the user (400) wears polarized glasses, the possibility that the second image displayed by the display system (10) appears dark can be reduced.
In a display system (10) according to an eleventh aspect, in any one of the sixth to tenth aspects, the display system further includes a reflection reducing member for reducing a reflection of light incident from outside the display system (10) that is generated on an inner surface of the translucent optical member (the first reflecting mirror 30 in the configuration of fig. 14, and the second reflecting mirror 40 in the other configuration).
According to this aspect, the contrast of the second image displayed by the display system (10) with respect to the map can be improved.
In a display system (10) according to a twelfth aspect, in the eleventh aspect, the image reducing member includes light-transmissive optical members (30, 40), and an inner surface of the light-transmissive optical members (30, 40) is disposed so as to obliquely intersect with an output direction of the light reflected by the final reflection surface (51).
According to this aspect, since the image reducing member can be configured to be highly accurate and uniform, the contrast of the second image displayed by the display system (10) with respect to the image can be further improved.
In a display system (10) according to a thirteenth aspect, in the eleventh or twelfth aspect, the image reducing member includes a reflection reducing member (75), and the reflection reducing member (75) is disposed in a direction in which light incident on the inner surface from the outside of the display system (10) in a direction opposite to the output direction of the light reflected by the final reflection surface (51) is reflected by the inner surface, and faces the translucent optical members (30, 40). The reflection reducing member (75) absorbs or scatters at least one of light.
According to this aspect, since the reflected light of the external light generated on the inner surface is absorbed or scattered, the contrast of the second image displayed by the display system (10) with respect to the image can be improved.
In a display system (10) according to a fourteenth aspect, in any one of the first to thirteenth aspects, at least a portion of each of the first reflective surface (31) and the second reflective surface (41, 601) is a curved surface.
According to this aspect, distortion of the image and the like can be corrected.
In a display system (10) according to a fifteenth aspect, in any one of the first to fourteenth aspects, a light control member (23) is further provided, and the light control member (23) is disposed on a display screen (21) of the display device (20) and controls an exit angle of light emitted from the display device (20).
According to this mode, the range of angles at which the second image displayed by the display system (10) can be viewed can be limited.
In the display system (10) according to claim 16, in any one of claims 1 to 15, the second image (300) is an image based on the partial image (P11) in the first image (P1).
According to this aspect, the range that can be seen as the second image changes according to the position of the eyes of the user (400).
In a display system (10) according to a seventeenth aspect, in the first or second aspect, the second reflecting surface (41, 601) is a surface having a light-transmissive translucent optical member (40) through which a part of incident light is transmitted, and reflected light from the final reflecting surface (51) is transmitted through the translucent optical member (40) and emitted to the outside of the display system (10). The length in the long side direction of the display device (20) is shorter than each of the length in the long side direction of the second reflection surface (41, 601) and the length in the long side direction of the final reflection surface (51). The length of the first reflecting surface (31) in the longitudinal direction is shorter than each of the length of the second reflecting surfaces (41, 601) in the longitudinal direction and the length of the final reflecting surface (51) in the longitudinal direction.
According to this aspect, the R-shape can be provided at the four corners of the translucent optical member (40) having the second reflecting surfaces (41, 601) and the final optical member (50) having the final reflecting surface (51), and therefore, the size can be reduced.
In a display system (10) according to an eighteenth aspect, in the seventeenth aspect, the length of the display device (20) in the longitudinal direction is shorter than the length of the first reflection surface (31) in the longitudinal direction, and the length of the second reflection surface (41, 601) in the longitudinal direction is equal to the length of the final reflection surface (51) in the longitudinal direction.
According to this aspect, the R-shape of the four corners of the translucent optical member (40) having the second reflecting surfaces (41, 601) and the final optical member (50) having the final reflecting surface (51) can be set further inward, and therefore, further downsizing can be achieved.
An electronic mirror system (80) according to a nineteenth aspect is provided with the display system (10) according to any one of the first to eighteenth aspects and an imaging unit (90). A display device (20) displays a first image based on the captured image of the imaging unit (90).
According to the embodiment, an electronic mirror system (80) can be provided, and the electronic mirror system (80) is provided with a display system (10) which can be miniaturized.
A moving object (100) according to a twentieth aspect includes the electron mirror system (80) according to the nineteenth aspect and a moving object body (110) on which the electron mirror system (80) is mounted.
According to this aspect, a mobile body (100) can be provided, and the mobile body (100) is provided with a display system (10) that can be miniaturized.
In a display system (10) according to a twenty-first aspect, in any one of the first to eighteenth aspects, a display screen (21) of a display device (20) and a first reflection surface (31) face each other across a range (200) through which light emitted from the display device (20) passes before reaching a final reflection surface (51). Here, the two surfaces facing each other across the range (200) is not limited to the two surfaces being arranged in parallel with each other, and the two surfaces may face each other across the range (200) in a non-parallel state.
According to this aspect, a display system (10) that can be miniaturized can be provided.
In a display system (10) according to a twenty-second aspect, in any one of the first to eighteenth aspects and the twenty-first aspect, the second reflecting surface (41, 601) and the final reflecting surface (51) face each other with the range (200) therebetween.
According to this aspect, a display system (10) that can be miniaturized can be provided.
In a display system (10) according to a twentieth aspect, in any one of the first to eighteenth aspects and the twenty-first to twenty-second aspects, optical paths (a13, a23) through which light propagates from the second reflecting surfaces (41, 601) to the final reflecting surface (51) are parallel to optical paths (a14, a24) through which light propagates from the final reflecting surface (51) to the second reflecting surfaces (41, 601).
According to this aspect, a display system (10) that can be miniaturized can be provided.
The configurations according to the third to eighteenth aspects and the twenty-first to twenty-third aspects are not essential to the display system (10) and can be omitted as appropriate.
Description of the reference numerals
10: a display system; 20: a display device; 21: displaying a picture; 23: a light control member; 30: a first mirror (first optical member, translucent optical member); 31: a first reflective surface; 40: a second reflecting mirror (second optical member, light-transmissive optical member); 40A, 40B: a substrate (light-transmitting optical member); 41. 601, a step of: a second reflective surface; 50: a final mirror (final optical component); 51: a final reflecting surface; 60: a polarizing element; 61. 62: an optical element; 63: a phase control member; 70. 70A: a housing; 74: a protrusion; 75: a reflection reducing member (image reducing member); 76: a half mirror (image reducing member); 80: an electronic mirror system; 90: an image pickup unit; 100: automobiles (moving bodies); 110: a movable body main body; 200: a range; 300: a second image; 400: a user; A11-A13, A21-A23: an optical path; p1: a first image; p11: and (4) partial images.

Claims (17)

1. A display system that displays a second image based on a first image displayed by a display device, the display system characterized in that,
having at least a first reflective surface and a second reflective surface on an optical path between the display device and a final reflective surface that reflects light emitted from the display device toward an outside of the display system,
the second reflecting surface is a surface of a light-transmitting optical member having light permeability for transmitting a part of incident light,
the first reflective surface reflects light emitted from the display device toward the second reflective surface,
the second reflecting surface reflects the reflected light from the first reflecting surface toward the final reflecting surface,
the reflected light from the final reflecting surface is transmitted through the light-transmitting optical member and emitted to the outside of the display system,
an optical path of light traveling from a display screen of the display device toward the first reflection surface intersects an optical path of light traveling from the second reflection surface toward the final reflection surface before the light emitted from the display device reaches the final reflection surface,
the light-transmitting optical member includes a substrate and a polarizing element,
and an optical element which is provided on the surface of the display screen and the surface of the polarizing element and imparts a phase difference of a quarter wavelength to the wavelength of the incident light in the direction of electric field vibration of the incident light.
2. A display system that displays a second image based on a first image displayed by a display device, the display system comprising:
the display device;
a first optical member that is disposed so as to face the display device and has a first reflecting surface that reflects first incident light from a display screen of the display device in a direction different from a direction in which the first incident light is incident;
a second optical member that is disposed so as to face the first reflection surface and has a second reflection surface that reflects second incident light from the first reflection surface in a direction different from a direction in which the second incident light is incident; and
a final optical member disposed so as to face the second reflecting surface, the final optical member having a final reflecting surface that reflects third incident light from the second reflecting surface,
wherein the second optical member includes a light transmissive optical member having light transmissivity for transmitting a part of incident light,
the reflected light from the final reflecting surface is transmitted through the second optical member and emitted to the outside of the display system,
the optical path of the first incident light intersects the optical path of the third incident light,
the light-transmitting optical member includes a substrate and a polarizing element,
and an optical element which is provided on the surface of the display screen and the surface of the polarizing element and imparts a phase difference of a quarter wavelength to the wavelength of the incident light in the direction of electric field vibration of the incident light.
3. The display system according to claim 1 or 2,
the display device emits light in a direction inclined with respect to a normal direction of the display screen.
4. The display system according to claim 3,
the final reflecting surface reflects light in a direction different from a direction in which light is incident from the second reflecting surface.
5. The display system according to claim 1 or 2,
light from the display screen of the display device is incident on the first reflecting surface without passing through the translucent optical member.
6. The display system according to claim 2,
the first incident light is emitted in a direction inclined with respect to a normal direction of the display screen,
the final reflecting surface reflects the third incident light toward a fourth direction different from a third direction in which the third incident light is incident from the second reflecting surface.
7. The display system according to claim 1 or 2,
the light-transmitting optical member further includes another light-transmitting substrate, and the polarizing element and the optical element provided on the surface of the polarizing element are sandwiched between the other light-transmitting substrate and the substrate.
8. The display system according to claim 6,
the optical element is disposed on a surface of the polarizing element on which light from the display device is incident,
a phase control member that imparts a phase difference of a quarter wavelength of incident light in an electric field oscillation direction of the incident light is disposed on a surface of the translucent optical member that is located outside the display system.
9. The display system according to claim 4,
further comprising a reflection reducing member for reducing a reflection of light incident from the outside of the display system on the inner surface of the light-transmissive optical member,
the image reducing member includes the light transmissive optical member, and the light transmissive optical member is disposed such that an inner surface thereof obliquely intersects with an output direction of the light reflected by the final reflecting surface.
10. The display system according to claim 4,
further comprising a reflection reducing member for reducing a reflection of light incident from the outside of the display system on the inner surface of the light-transmissive optical member,
the reflection reducing member includes a reflection reducing member that is disposed in a direction in which light incident on the inner surface from outside the display system in an output direction of the light reflected by the final reflection surface is reflected by the inner surface, and faces the light transmissive optical member,
the reflection reducing member absorbs or scatters at least one of light.
11. The display system according to claim 1 or 2,
at least a portion of each of the first and second reflective surfaces is a curved surface.
12. The display system according to claim 1 or 2,
the display device further includes a light control member that is disposed on the display screen of the display device and limits an exit angle of light emitted from the display device within a predetermined allowable angle range.
13. The display system according to claim 1 or 2,
the second image is an image based on the partial image in the first image.
14. The display system according to claim 1 or 2,
a length in a long side direction of the display device is shorter than a length in a long side direction of the second reflection surface and a length in a long side direction of the final reflection surface,
the length of the first reflecting surface in the longitudinal direction is shorter than the length of the second reflecting surface in the longitudinal direction and the length of the final reflecting surface in the longitudinal direction,
the length of the first reflection surface in the long side direction is longer than the length of the display device in the long side direction.
15. The display system of claim 14,
the length in the long side direction of the display device is shorter than the length in the long side direction of the first reflection surface, and the length in the long side direction of the second reflection surface is equal to the length in the long side direction of the final reflection surface.
16. An electronic mirror system comprising:
the display system of any one of claims 1-15; and
an image pickup unit for picking up an image of a subject,
wherein the display apparatus displays the first image based on the captured image of the imaging section.
17. A movable body characterized by comprising:
an electron mirror system according to claim 16; and
and a movable body main body on which the electron mirror system is mounted.
CN201910812410.9A 2018-08-30 2019-08-30 Display system, electron mirror system, and moving object Active CN110873954B (en)

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Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112622767A (en) 2019-10-08 2021-04-09 松下知识产权经营株式会社 Display system and electronic rearview mirror system provided with same
DE102020128073B4 (en) 2019-10-30 2024-03-21 Panasonic Intellectual Property Management Co., Ltd. Display system
US11366311B2 (en) 2020-04-01 2022-06-21 Panasonic Intellectual Property Management Co., Ltd. Display device
JP7002021B2 (en) * 2020-05-12 2022-01-20 パナソニックＩｐマネジメント株式会社 Display device
CN113885247B (en) * 2020-07-03 2024-03-01 松下知识产权经营株式会社 Display system
CN115857165A (en) * 2021-06-30 2023-03-28 上海天马微电子有限公司 Head-up display

Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH02204714A (en) * 1989-02-02 1990-08-14 Nippondenso Co Ltd Hologram display device
JPH07309152A (en) * 1994-05-16 1995-11-28 Yazaki Corp Display device for vehicle
JP2008296635A (en) * 2007-05-29 2008-12-11 Calsonic Kansei Corp Vehicular display
WO2010050012A1 (en) * 2008-10-29 2010-05-06 京セラ株式会社 Camera module mounted on a car
WO2016079927A1 (en) * 2014-11-19 2016-05-26 パナソニックＩｐマネジメント株式会社 Head-up display and vehicle
JP6024452B2 (en) * 2012-12-28 2016-11-16 株式会社Ｊｖｃケンウッド Image display device
CN107003526A (en) * 2015-03-19 2017-08-01 松下知识产权经营株式会社 Head-up display
JP2018036336A (en) * 2016-08-29 2018-03-08 京セラ株式会社 Light source device, display device and mobile body
JP6372346B2 (en) * 2014-12-24 2018-08-15 日本精機株式会社 Head-up display

Family Cites Families (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB9012667D0 (en) * 1990-06-07 1990-08-01 Emi Plc Thorn Apparatus for displaying an image
JP5286750B2 (en) 2007-11-16 2013-09-11 日産自動車株式会社 Vehicle display device
JPWO2015159523A1 (en) * 2014-04-14 2017-04-13 パナソニックＩｐマネジメント株式会社 Head-up display and mobile body equipped with head-up display
US9823472B2 (en) * 2015-07-17 2017-11-21 Lg Electronics Inc. Head up display for vehicle
DE112016005488B4 (en) * 2015-12-01 2021-11-25 Panasonic Intellectual Property Management Co., Ltd. Head-up display and mobile object equipped with a head-up display
CN106932898A (en) * 2015-12-30 2017-07-07 光宝科技股份有限公司 Head-up display device
EP3264160B1 (en) * 2016-03-24 2019-08-28 Panasonic Intellectual Property Management Co., Ltd. Headup display device and vehicle
WO2017163288A1 (en) * 2016-03-24 2017-09-28 パナソニックＩｐマネジメント株式会社 Headup display device and vehicle
JP2017210229A (en) 2016-05-18 2017-11-30 株式会社Ｊｖｃケンウッド Display device for vehicle and display system for vehicle
JP6857800B2 (en) * 2016-12-21 2021-04-14 パナソニックＩｐマネジメント株式会社 Virtual image display device
US10525886B2 (en) 2017-05-31 2020-01-07 Panasonic Intellectual Property Management Co., Ltd. Display system, electronic mirror system and movable-body apparatus equipped with the same
DE102019106738B4 (en) * 2018-03-27 2021-11-04 Panasonic Intellectual Property Management Co., Ltd. Display system, electronic mirror system, moving vehicle and display method

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH02204714A (en) * 1989-02-02 1990-08-14 Nippondenso Co Ltd Hologram display device
JPH07309152A (en) * 1994-05-16 1995-11-28 Yazaki Corp Display device for vehicle
JP2008296635A (en) * 2007-05-29 2008-12-11 Calsonic Kansei Corp Vehicular display
WO2010050012A1 (en) * 2008-10-29 2010-05-06 京セラ株式会社 Camera module mounted on a car
JP6024452B2 (en) * 2012-12-28 2016-11-16 株式会社Ｊｖｃケンウッド Image display device
WO2016079927A1 (en) * 2014-11-19 2016-05-26 パナソニックＩｐマネジメント株式会社 Head-up display and vehicle
JP6372346B2 (en) * 2014-12-24 2018-08-15 日本精機株式会社 Head-up display
CN107003526A (en) * 2015-03-19 2017-08-01 松下知识产权经营株式会社 Head-up display
JP2018036336A (en) * 2016-08-29 2018-03-08 京セラ株式会社 Light source device, display device and mobile body

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